I'm not sure we can attribute this inaction to much more than the established Democrats actually stand to personally benefit from these policies. They don't really have a reason to push back because their donors are the same people in most cases (there are a few exceptions) and so many of them have the same level of gerrymandering and name recognition in their districts as the opposition.

This is not a statement that both parties are the same. They demonstratively are not as Democrats won't typically be the ones to enact these policies but they also don't really have a reason to stop them either since things like the tax breaks personally benefit them.